Mechanical stoker.



o. WUNDRACK.

MECHANICAL STOKER.

APPLrcATloN man oc1.12,1914.

1,163,965, Patented Dec. 1915.

4 SHEETS--SHEET l.

0. WUNDHACK.

MECHANICAL STOKER.

APPucATloN man 001.12.1914.

Patented Dc. r7, 1915.

www@

- 4 SHEETS-SHEET 2.

www

0. WUNDRACK. MECHANICAL STOKER.

APPLICATION HLED 001.. 12. 19m.

Pam-tedi- De. 7, 1915. 4 SHEETS-SHEET 3 Mmmm mm, m, amm. QQ NS MQ QQ fojwuNDRACK.

MECHANICAL sToKER. APPLICATION FILED 001.12. |914.

Patented Dec. 7, 1915.

SHEETS-SHEET 4.

OTTO WUNDRACK, 0F MAYWOOID, ILLINOIS.

MECHANICAL STOKIER.

Liaaaca.

Specification of Letters Patent.

Patented Dec.' 7, 19115'.

Application led October 12, 1914:. Serial No. 866,264.

.and useful Improvements in Mechanical Strikers; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the ac'- companying drawings, and to the letters of reference marked thereon, which form. a

npart of this specification.

This invention relates to improvements in mechanical' stokers for furnaces and consists of the matters hereinafter describedv and more particularly pointed out in the appended claims.

The object of the invention is to provide a simple and eflicient mechanism for feeding the fuel-evenly over the grate surface, together with means whereby the amount of fuel'admitted or fed to the grate may be regulated as required without stopping the operation of the stoker.

Other objects andI advantages will appear as I proceed with my specification.

In the drawings: Figure 1 is a view in vfront elevation of a stoker made in accord ance with my invention, illustrating the same in a position for feeding fuel to the interior of a furnace. Fig. 2 is a longitudinal vertical sectional view through a furnace to which my improved stoker has been applied, the plane of the section being indicated by line 2-2 of Fig. 1. Fig. 3 is a detail sectional .view on an enlarged scale,

the plane of the section being indicated by line -3-3 of Fig. 1. Fig. 4 is a detail sectional view, 4the plane of the section being indicated by line 4 1 of Fig. 3. Fig. 5 is a detail sectional View on an enlarged scale the plane of the section being vindicated by.

linel 5 5 of Fig. 2. Fig. 6 is a detail longitudinal vertical .sectional view on an en` lar-ged scale through the grate bars at the lower inner end of the stoker. Figs. 7, 8- and 9 respectively are face views in elevation of several of the fuel-feed controlling disks which will be more specifically referred to as I proceed with my specification.`

Referring now to that embodiment ofmy invention as illustrated in the accompanying drawings :-The furnace (see Fig. 2') in 4connection with which my improvements are shown herein, is of theopen front type,

which open front is closed by the front wall vof the stoker when said stoker is in operative position in the furnace. Said furnace 1s provided with an arch wall 10 and with an overhanging bridge wall 11 the space between the arch -wall and the top of the bridge wallcbnstituting a conduit by which the hot gases from the combustion chamber l2 are directed into contact with the usual boiler of the plant of which the furnace forms a part. The furnace has an ash pit 13 the bottom of which is preferably located below the floor level of the engine room where the furnace-.is located and which extends outwardly beyond the open front of the furnace a suitable distance.

arranged that their inner faces are fiush with the inner faces of the side walls of the furnace when the stoker is in operative porigidly attached to a front wall plate' 17 'l which is adapted to close the open front ofl the furnace, with its lateral marginal parts engaging against and overlapping the front ends of the furnace side walls.

The side frame members 15,*the channel 16 and the front plate 17 together constitute a carriage upon which the various operative parts of the stoker are supported. The rear end of said carriage is provided with flanged wheels 19-19 which are mounted upn stub shafts 20 that are Xed to and extend inwardly from the side frame members 15. The front end of said carriage is likewise provided with anged wheels 21 mounted upon similarlyv supported stub shafts 22 near the forward ends o'f the frame members '15. The wheels 19 and 21 roll upon rails 23 ions 25 fixed to the inner ends of horizontally extending Shafts 26 that have rotative bearing in the front wall 17 of the stoker carriage. The opposite ends of said shafts project outwardly from the-front face of the plate 17 and are each squared'to receive a.

wrench, byl means 'of which the associated y shaft may be rotated.l Manifestly, by rotating said shaft the stoker may be withdrawn,

throughthe operation of the gearing from Athe interior ofthe furnace.

At the sides'f'of` 'the Stoker frame are located bars27-e-27, having hooks 2S by means of which they are hinged to swing up and down on lugs 29'fixed to the rear face f the Stoker front wall 17 at about the level of the top of the bridge wall 11. Saidfbars`27 constitute supports forthe gratefbarsjand are inclined downwardly and rearwardly toward the bridge wall and terminate in horizontal n extensions 30 which project into the vicinity of the over hanging ledge of the bridge wall;`

11. The ends of said horizontal' extensions `rest upon a transversely extending, flat bar or support 31, which in turn rests at its ends upon upright adjusting screws 32. The

said screws are threaded through horizontal j flanges '33 on the side frame members Lock nuts 34, are provided on' said screws 32 to hold them against rotation after they have beeIr adjusted to bring the supporting f the lugs 29. Such flexibility is of advantage any inequalities due to the construction of the furnace and also to give the required in-` i clination to the grate supported by said bars for proper feeding of the fuel over said for purposes of adjustment where there are grate.

The bars v27 are provided with upwardly opening -notches 36 adapted to receive and form bearings for trunnions 38 formed at the ends of transversely extending rocking grate bars 37. Each grate bar 37 has a plurality of parallel, spaced, rearwardly extending short bars 39 which extend into the vicinity ofthe next adjacent grate bar to the rear' and which, together with the bar 37, constitute a sectionalI grating, the whole number of the sectional gratings thus formed comprising the grate of the stoker. Each grate bar 37 is also provided at its endswith downwardly extendinfv rock-arms 40-40 and the rock-arms of a l the sectional gratings are 'pivotally connected to inclined links 41, 41, one of said links being at one side of the Stoker, and the other at the opposite side thereof. A connecting rod 42 is attached to each link 41, the outer end of said connecting rod projecting through suitable openings in the front plate 17 and being there provided with an eccentric strap 43. Each strap 43 embraces an associated eccentric disk 44 that is rigidly attached to and masses rotates with ahorizontal shaft 45, extending transversely in front of the Stoker, andv mounted in suitable 4bearing.blocks 46 fixed to the front wall plate 17 thereof. The shaft 45 projects at one end -beyond the lateral edge of the front wall plate 17 and has vxed to it at that end, a ratchet wheel 47. Adjacent said ratchet wheel 47 and having bearing thereon, is located a rocking bell cranklever 48 with a vertical arm carrying a pawl49 adapted forfengagement with the YteethofA the ratchet wheel 47 and a horizontal arm provided with a slot 50 in which is mounted a bearing block 52 that is pivotally -connected to a vertically' reciprocating rod 51. The bearing block 52 is capable of adjustment wit-hinthe slot50 of the bell crank vlever sothatthe throw7 of said lever may be regulated,--thus controlling-the rotative speed of the shaft '45.'v It is apparent that vertical reciprbcation of the rod 5l will cause a rocking movement of the bell crank `lever 48 and the said rocking movement will impart to the Shaft 45 a rotative vstep by step. movement through the action of the pawl 49 and the ratchet wheel. 47. The rotation of the shaft 45 will, through the cccentrics 44-4-4, produce a reciprocating movement of the rods .42 and links 41 to which the rock arms 39 of the grate bars 37 are pivotally connected, and a resulting rocking movement of the sectional gratings comprised by thegrate bars 38 and the bars 39. The rocking of the sectional gratings will cause the `fuel on the inclined grate of thev Stoker to beadvanced downwardly and rearwardlyand; manifestly this advance of the fuel may be soadjusted that, when the fuel reaches the rear end of. the grate it will be 1 -thordughly' burned, leaving only a residue. of ash.

It is desirable to remove the ash left at the rear of the grate from the`-co1nbustion chamber at certain times and also to break up any clinke-rs or the like left at the rear of the grate without interfering with the continuous feed of fuel over thegrate.

Suchmeans are provided as follows:

55 indicates a hand controlled clinker breaking bar which when in one position forms a part of the grate surface. Said bar (see Figs. 1, 5 and 6) comprises a plurality. of spaced, sector` plates-56 placed in between the short bars 39 of the lowermost sectional grating.` Said sector plates are madesintegral with a rock bar 57 the ends of` which are provided with trunnions 59 having suitablebearing in notches 36 formed in the upper edges of'the grate supporting bars 27 near the lower end thereof. 60-60 indicate downwardly extending rock arms rigidly attached' to the rock bars The said rock arms are pivotally connected to inclined operating rods 61 which project through apertures.62 formed in the front wall 17 of tilt Licence gagementfwith thel bottom wallof the `assodated-aperture 63' through whichit extends,

A"ttf/hold" said clinker bar in fixed position.

The forward end of each bar 62 is Aprovided with a hand loop 64 for convenience in operating said rod.

65 indicates` an ash and clinker holding and supporting grate. Said ash grate is arranged to receive the burnt fuel' after the samev has traveled overl and has been discharged from the grate bars 37. Said ash grate comprises a horizontal rectangular frame 66 the end members of which are connected by integral grate bars 67. The front end transverse member of said grate extends into the vicinity of and adjacent the bar 57 of the clinker member. The rear end transverse member extends into the vicinity. of the vertical plane of the overhanging ledge of the bridge wall 11 and said frame member is provided with trunnions 68 which have bearing in upwardly opening notches 69 formed in the upper edge ofthe horizontal extensions 30 of the grate supporting bars 27. To the forward end member of the grate 65 are attached downwardly and forwardly extending arms 70 which are pivotally attached to operating and'supporting bars 71. Said bars extend upwardly and forwardlyvand project through suitable apertures in the front plate 17. Said bars-are likewise providedl with notches in their lower edges which coact with the bottom walls of the aperture inthe front wall through which they pass in the same -way as in the case of the bars 61. The forward ends of the bars 71 are likewise provided with hand loops 72.

When it is desired to relieve the rearmost sectional grating of the 'stoker grate of its accumulated cinders and ashes and to break up theclinker formation thereon, the bar 61 is raised to disengage it and is then reciprocated forwardly and backwardly to -rock the clinker grate bar 55 from the position shown Fig. 2 to that shown in Figt. This rocking movement of said grate bar vwill break and raise such clinkers as will have formed at this point and depositthe.A

greater amount ofA them upon the ash grate 65. When itis desired' to dump `the ash grate the clinker bar 55 is leftin the position shown in Fig. 6.. When in this posiL tion said bar forms an abutment or stop for.

holding back the fuel .upon the inclined grate of the Stoker. rThe hand lever 71 supporting vand holdin the forward end of the ash grate, is move upwardly-to disengage it and is thenmoved rearwardly, thus pere mitting the forward end of said grate to drop or swing about upon its trunnions 68. rl`his movement will incline the forward end of' said grate downwardly and the ashes, clinkers and the like thereon, will then fall into the ash pit 13. The ash grate 65 is then returned to its normal position as shown in Fig. 2. Y

To remove the ashes fromthe ash pit the front wall plate 17 is provided with a door 75 which is adapted to swing downwardly about its bottom edge to' open for the admission of the usual pull ironor hoe for the4 removal of the ashes from the lash pit. When the ashes have been removed from the ash pit; the door 75 is then closed. l

The front plate 17 4of the Stoker is also provided just above the door 75 with doors 7 6j Said doors 76 are of a greater height than the door 75 and swing Yabout vertical axes to be opened and closed and permit of an inspection of' the under surface of the grate bars 38. Said doors may be alsoA used toy controlthe draft of air admitted to the interiorv ofthe furnace.

The means for feeding fuel to the grate of the Stoker are as follows: To the upper end of the front wall plate 17 is attached and supported a fuel hopper 80. Said hopper` comprises an upwardly and outwardly in clined front wall '81,. uprightv side walls 82--82 and an upright rear wall 83. The

rear-wall 83 is spaced a suitable distance inwardly from the front wall plate 17 and when the Stoker is in operative position relative to the furnace to which it is applied,

.said wall will abut against the front of the4 'throatarch-l()at of the arch wall with its lower edge ata level approximating the level of the throat arch 108x The lower inner end of the front wall 81 is made in arcuate form as at 84. '85 indicates a vtransversely extendu ing plate which is attached at its upper edge to therearvplate '83 of the hopper.. Said plate is provided with a downwardly and forwardlyincli'ned portion 86 which terminates short of the plate 81l l'to' form a disch-argeiopeningv 80a and an arcuate portion 87, said arcuate portions 84C and 87 respectively forming an auxiliary hopper 88, which communicateswith the main hopper 80 by means of said discharge opening 80a. The inner end of the arcuate portion 84 of the plate 81 terminates short of thelower edge of the yplate 85 to form a discharge passage or opening .89 connecting said auxiliary hopper-"88 with the interior of the furnace.

- vConcentrically arranged with respect to the arcuate wallsfl and 87 of the said auxiliary hopper islocated a square shaft 90 the ends of ywhich are cylindrical and which have suitable bearing in the end plates 82 of the main hopper in a manner permitting rotationof said shaft.l Mounted on said shaft 90 intermediate the side walls 82 of the hopper so as to rotate therewith is located a star feed device 91 having four concave side walls 91a which form pockets each capable of holding a certain amount of fuel as it vfalls from the'main hopper 80 through the discharge iae opening 80a at the bottom thereof. It is ap-d parent that with the rotation qf thelshaft 90 the Vfeed device 91 will discharge the fuel lat a certain regular rate through the disj @fits end'and the bearing 92 is aratchet wheel 493, Adjacent the outer face of said ratchet 'wheel and loosely mounted on said shaft Ais charge opening 89 at the bottom of said auxiliary hopper 88 upon the 'grate of the stoker. The feed -device 91 is adapted for rotative lmovement in a step' by step manner and the means for imparting such step by step rotaa bell crank lever 94 having a hub 94a. The said bell ci ank lever comprises a vertical arm 95 and a horizontally extending arm .100.; The vertical arm 95 of said bell crank lever carries a pivoted pawl 96 which is l0- cated in the vertical plane of and adapted to intermittently engage` and actuate the,

ratchet wheel'93. Said vertical arm also carries on its other side a second pawl 97 which engages with and actuates a second ratchet wheel 98 of smaller diameter, loosely mounted upon the hub 94u of the bell crank lever 94. vA collar 99 fixed to the end of the shaft '91 retains said pawls and bell crank lever from endwise displacement upon said The horizontal arm 100 of said bell crank lever projects forwardly beyond the plane of the front wall plate 17 and is provided with,l a slot 101 near its forward end. In

said slot is adjust-ably mounted a bearing block 102 towhich is pivotally connected the upper end of a vertically reciprocating rod 103. The reciprocating movement of said rod produces a rocking movement of said bell crank lever 94 about the shaft 91- as an axis.

, Fixed to the outer face of the ratchet wheel 98 by means of suitable bolts 98a is a plurality of superposed feed controlling disks 105, 106, 107 and 108. (See Figs. 3, 7, 8. and 9 respectively), each of which has a different peripheral contour. As shown in F ig.3, the disk 105 is provided upon its pe'- -riphery with equally spaced teeth or lugs 105a with like shaped depre'ions 105b between them.

110 indicates a horizontally. extending square bar which is .adjustably mounted in a square opening formed in the pawl 96.

Said har may be adjusted inwardly and out,

wardly through said pawl 96 and locked in the desired position therein. by means of a ffy nut 111. The outer end' of said bar 110 is provided with an angularly finger 1 10a which is adapted te engage the pe .riphery of any of the desired feeding disks 105, 106, 107 and 108, depending upon the adjustment of the bar 110. The linger 110 is so proportioned with respect to the pawl 96, that when itsfree end is in engagement with one of the depressions 105b of the disk 105 the pawl 96 will rotate about its pivot and engage one of the teeth of the ratchet wheel 93. Duringthe rotation of the ratchet wheel 98 and with it the several feed controlling disks before mentioned, the finger llOwill ride upon one of the teeth 105 of the disk 105 causing the free end of said linger to engage and carry with it the pawl 96 so as to disengage the same from the teeth of the ratchet wheel 96. i

The operation of the feed mechanism is as follows: As before explained the vertical reciprocation of the.rod.103 will cause the bell crank lever 94 to rock or oscillate about its axis. .This rocking movement will cause the pawl 97 to engage with one of the teeth ff the ratchet wheel when the vertical arm of saidvlever is moving forward, and rotate said wheel a distance equal the distance between adjacent teeth. When the arm moves rearwardly the aWl 97 will drag over the inclined face cip the succeeding tooth and will engage the radial face of said tooth so that when the vertical arm again moves forward the wheel will again be advanced the distance ofone tooth. The ratchet wheel in l this manner is given a step by step rotative movement 'and the disks' 105, 106, 107 and 108 will be advanced a like radial distance. When the linger 110a is engaged within any of the recesses 105b of the disk 105 the pawl 96 on the vertical arm 95 will be in engagement with the tooth of the ratchet wheel 93 and on the forward movement of said arm said pawl will advance the ratchet wheel a distance of one tooth. Said ratchet wheel being keved'to the shaft 91 will rotate the same'a radial distance equal one tooth. On the rearward rockin movement of the vertical arm 95 of the ell crank lever 94 the paw] 97 will drag over the now stationary ratchet wheel -98 and the finger 110a will valso drag or-ride over the tooth 105. This dragging movement will cause the pawl 96 to be lifted upwardly aboutits axis so that when the finger. l10n. is engaging the top of the tooth 105a said pawl will be free from engagement with the ratchet wheel 93. Should the bar 110 be adjusted through the pawl 96 so that-the finger would be in engagement with the top surface of one of the broad teeth 106A of the disk 106 said pawl will be held out of engagement with the teeth ofthe ratchet wheel 93 as long as the finger 110 -is in contat with the top of said teeth.

When the finger 110a is in engagement with the depression 106b of said disk said pawl' 96 would'be in engagement with one of the teeth of the ratchet wheel 93 and upon a for ward movement of said arm the said wheel and shaft v91 would then be rotated forwardly ,one step. 1 have illustrated the disks 107-108 as having different shaped or length of teeth 1072, 108, separating said teeth. 1t is apparent thatthe teeth and depressions may be arranged so that any kind of desired feed of fuel may be delivered to the stoker, such feed of course depending upon the contour of the feed disks. As the fuel is fed from thev auxiliary-hopper 88 through its discharge opening 89' said fuel falls upon an inclined transversely extend ing plate120. "Said plate is pivotally supported at its forward edge on 4a rod 121 which is fixed at its ends in the side walls 82 of the main hopper 8O ata point below the arcuate wall 81 of the auxiliary hopper 88. The said plate extends rearwardly and downwardly from its pivotal axis and the free edge thereof is arranged to overlap the forward end of the stoker grate. Fixed to saidplate 120 adjacent the rod 121 are laterally arranged forwardly extending bars 112 which extend through suitable slots formed in the front wall plate 17. Said bars are provided with adjustably mounted weights 113 so arranged upon said bars asl to approximately counterbalance the weight of the plate 120.

- 114C indicates a downwardly and rearwardly inclined plate, which is pivotally mounted adjacent its front edge upon ears 115 fixed to the front plate 17. The rear free edge of said plate projects into the vicinity of and is arranged to Support the free edge of the plate 120. l

Should it be desired to view the interior of the furnace or to momentarily shut off the feed of fuel from the hopper 80 with-out stopping the operation of the stoker, said'plate 120 may be swung upwardly to the position indicated in dotted lines in Fig. 2 so as to close od the feed of fuel from the auxiliary hopper by exerting a downward pressure upon the rods 112. When said plate 110 is in the position noted, a door 115 provided in the front plate 17 may be opened, when full view may be had of the interior of the furnace.

While in describing my invention I have referred to certain details of lmechanical construction and arrangement of parts, 1 do not wish to be limited thereto except as may be pointed out in the appended claims.

1 claim as my invention:

1. In combination with a stoker, means for feeding fuel to said stoker, comprising a hopper, a rotative shaft,'a fuel feeding device for delivering fuel from the hopper to the stoker fixed on said shaft, a ratchet wheel fixed to said shaft, a second ratchet wheel loosely mounted on said shaft, a rock arm, pawls carried by said arm adapted for engagement with said ratchet wheels, and

flxed to said shaft, a second ratchet wheel' loosely mounted on said shaft, a rock arm, pawls carried by said arm adapted for engagement with said ratchet wheels, and means carried by the said loosely mounted ratchet wheel for ,controlling the operative engagement of one of said pawls with respect to the said fixed ratchet wheel.

3. 1n combination with a stoker, means for feeding fuel to said stoker comprising a hopper, a rotative shaft, a fuel feeding device for delivering fuel from the hopper to the stoker fixed on said shaft, a ratchet wheel fixed to said shaft, a second ratchet wheel loosely mounted on said shaft, a rock arm, pawls carried by said arm adapted for engagement with said ratchet wheels, and means whereby said controlling means may be varied.

1n testimony, thatl claim the foregoing as my invention 1 affix my signature in the presence of two witnesses, this 20th day of September, A. D. 1914.

OTTO VVUNDRACK.

Witnesses:

T. H. ALFRnDs, KARL W. DOLL. 

